Astronauts on the seven-month trip to Mars are at increased risk of becoming deaf and suffering from balance problems, says new study.
Researchers at the Medical University of South Carolina used MRS analyzes to discover that long space missions can cause fluid to build up in the ear.
A build-up of fluid in the ear can cause hearing loss and dizziness – a condition called “mastoid effusions” – impacting the bone at the back of the ear.
Donald Trump wants the first manned Mars mission to take place by 2033. The trip will take approximately seven months – longer than the astronauts currently stay on the ISS.
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Astronauts on the International Space Station spend an average of six months in space. The new study found that this puts them at greater risk of ear disease that could cause deafness. This is a photo of Christina Koch in space – but is not related to this study
The study involved MRI scans of 35 astronauts – 17 from the NASA space shuttle program team and 18 of them having spent time on the International Space Station.
Traveling outside Earth’s atmosphere to regions beyond has long been compared to pear-headed – because of zero gravity, the researchers say.
One study found that astronauts on six-month expeditions (ISSs) were nine times more likely to suffer from a condition called “mastoid effusions.”
This was compared to those who participated in shorter space shuttle missions of around two weeks.
The mastoid bone is at the back of the ear and contains air cells vital for hearing – when fluid builds up in this area, it can cause pain and impaired faculties.
Corresponding author Dr. Donna Roberts of the Medical University of South Carolina said there was a direct link between ISS conditions and mastoid effusions.
Head congestion is one of the most common symptoms encountered by astronauts when their nose, ears and eyes become blocked with fluid.
Space flight leads to more than three and a half liters of blood moving upwards, from the bottom to the top of the body.
The study published in JAMA Otolaryngology – Head & Neck Surgery is the first to measure the effect on cells of the mastoid air in the sinuses.
No difference was found in the sinuses of the study astronauts.
However, long duration spaceflight was associated with a 9.28 higher probability of mastoid effusion than short duration.
This may be due to the fact that it damages the tubes and vessels that connect the inner ear to the back of the throat and head, explained Dr. Roberts.
She said that at zero gravity, astronauts experience nasal congestion and head pressure, but there is little data regarding physiological changes in the nasal sinuses or mastoid air cells.
NASA has avoided the use of computed tomography (CT) to limit the dose of radiation received by astronauts, given the exposure they experience during space flights.
But, as part of the routine medical protocol, they all have an MRI of the head before and after the flight.
His team took advantage of this by examining these scans – all of which were obtained before and after the space shuttle or ISS missions.
“Long-term spaceflight on the ISS is associated with an increased incidence of mastoid effusions,” said Roberts.
“The cause of this phenomenon is probably multifactorial, but the possible explanations may reflect several conditions associated with the effusions observed on Earth.
“Further investigation is needed to provide a definitive explanation for the development of these effusions and to determine if these results can be applied to more than this small population of astronauts.”
The study compared the astronauts’ analyzes of the two-week space shuttle missions to those of the International Space Station astronauts who spent approximately six months in space.
International Space Station astronauts who spend more than six months in space have a 9-fold increased risk of developing an inner ear condition that could lead to deafness
Dr. Michael Stenger, of the NASA human research program, who was not involved in the study, said the consequences needed to be better understood by space doctors.
New medical requirements will be needed for future exploration missions far from Earth, Stenger siad.
Indeed, a mastoid effusion could increase the risk of debilitating hearing pain.
“On the ISS, in the event of a medical emergency, astronauts can desorb and be treated relatively quickly, within a few hours.
“On a mission to the Moon or to Mars, treatment would be limited to the supplies and techniques available on the vehicle.”
Possible remedies include simulating Earth such as gravity on the spacecraft Mars or the thigh cuffs which can trap blood in the legs.
“The space and medical research community is actively working to identify the appropriate extent and duration of these countermeasures,” said Stenger.
“This work becomes more and more important as we discover new consequences of long-duration space flights.”
He said it was an exciting time in human space flight with the advent of commercial operators and the next manned missions to the Moon.
“Although 50 years have passed since Apollo 11 landed on the moon and 20 years since humans began to reside permanently on the ISS, researchers continue to make new discoveries about the human body in space, “said Stenger.
The results were published in the journal JAMA Otolaryngology – Head and neck surgery.
HOW DOES RADIATION SPACE IMPACT ON THE HEALTH OF ASTRONAUTS?
Astronauts traveling to Mars would likely be bombed with 700 times the radiation levels experienced on Earth.
Even aboard the International Space Station, astronauts are exposed to 200 times more radiation from their work than an airline pilot or a radiology nurse would do.
As a result, NASA continuously monitors local space weather information.
If an explosion of space radiation is detected, mission control in Houston, Texas, may ask astronauts to interrupt space walks, move to more protected areas of the orbiting laboratory, and even adjust the altitude of the station to minimize any impact on health.
The activity of solar flares can cause acute effects of radiation exposure – such as changes in the blood, diarrhea, nausea and vomiting – which can be recovered and other impacts which are not reversible and / or deadly.
The long-term bombardment of cosmic rays is a greater concern.
This can increase the risk of cancer, generate cataracts and cause infertility.
It can also damage the brain, central nervous system and the heart, paving the way for various degenerative diseases.
Changes in DNA due to space radiation can even be passed on to subsequent children.